Experimental and molecular simulation studies on adsorption and diffusion of elemental mercury in flexible UiO-66

• Published in: Fuel (Guildford) Vol. 325; p. 124989
• Main Authors: Xu, Yueyang, Qi, Hu, Guo, Konglu, Xue, Jianmin, Zhu, Fahua, Zhong, Zhaoping, Zeng, Yongping
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2022
• Subjects: Adsorption; Diffusion; Elemental mercury; UiO-66; Elemental mercury; UiO-66; Adsorption; Diffusion
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2022.124989

[Display omitted] •Adsorption and diffusion of Hg0 in UiO-66 was investigated by molecular simulations combined with experiments.•A good agreement was obtained between experimental data and molecular simulations.•The dynamical and structural properties of Hg0 in UiO-66 were used to interpret the adsorption mechanism. Adsorption of elemental mercury (Hg0) in flue gas using the porous materials is a promising technology. We conducted the molecular simulations and experiments of the adsorption and diffusion of Hg0 in UiO-66 at 393 K. The calculated adsorption isotherms using GCMC simulation are in good agreement with the experimental data. The flexible force field for UiO-66 is reasonable for the study of the thermodynamic and dynamic properties of Hg0 in this structure. The free energy and density distribution of Hg0 were performed, and showed that Hg0 was preferentially located in the tetrahedral cages in UiO-66. The dynamic properties of the Hg0 in the flexible UiO-66 were studied by molecular dynamics. The diffusion mechanism can be explained by the inter-cage hopping events. A lower decay of the VACFs for Hg0 in the flexible UiO-66 was observed at the higher loading. Further analysis of the radial distribution functions, Hg0 molecules are found with higher probability near the O1 atoms of the tetrahedral cage in the framework. Based on structural and dynamics properties, we achieve a fundamental insight into adsorption mechanism. We anticipate these results could provide insights into the adsorption and diffusion of Hg0 for the development of new porous materials.